Pulley



H. E. PRINTZ.

PULLEY. APPLICATION FILED APR. 15, [920.

Patented APR-19,1921.

UNH'I'ED STATES HAROLD E. PRINTZ, OF READING, PENNSYLVANIA,

ASSIGNOR TO READING WOOD SYLVANIA.

PULLEY.

To all whom it may concern:

Be it known that I, HAROLD E. PRIN'rz, a citizen of the United States, residing in Reading, Pennsylvania, have invented Pulleys, of which the following is a specification.

One object of my invention is to provide a pulley of such construction as shall be capable of causing its cooperating belt to remain centrally upon it under operating conditions without requiring it to be crowned, the invention contemplating a pulley which shall prevent slipping and stretching of the edges of the belt.

I further desire to provide a belt pulley which shall include elements or means whereby lateral shifting of the belt operative upon it is efiectually prevented, the pulley itself being substantial in construction, durable and inexpensive to make.

These objects and other advantageous ends I attain as hereinafter set forth, refe"- ence being had to the accompanying drawings, in which,

Figures 1 and 2 are respectively a front and an end elevation ofa pulley constructed in accordance with my invention;

Fig. 3 is a vertical section on the line 3-3, Fig. 1

Figs 4 and 5 are respectively a front and an end elevation illustrating a pulley made in accordance with my invention; and

Fig. 6 is a fragmentary elevation of the surface of one of my pulleys under operating conditions.

In the above drawings 1 represents the shaft-receiving bushing of a pulley having a built up wooden body 2-rigidly and immovably connected to it, in the presentinstance by radial screws 3. In accordance with my invention the wooden body of the pulley is built up of a series of relatively thick disks or sections 4 of a wood such as hard cross grain maple, ash, oak or beech, alternated with thinner disks or sections 5 of relatively harder wood such as end grain maple. In the present instance each of the harder sections is made up of two sheets of veneer, although obviously one or more than two of such sheets or laminations may be employed without departing from my invention.

If two or more of such sheets of veneer are employed, they are so placed that their grain runs in different directions, preferably 7 at right angles.

Specification of Letters'Patent. Patentd .Apr, 19 1921 Application filed April 15, 1920.

Serial No. 374,048.

V The various laminations constituting the body of the pulley are glued together and such glue is allowed to set under heavy pressure, the sections being held together by any suitable number of bolts or screws 6 extending through them in lines parallel to the axis of the pulley.

If desired the pulley after being constructed as illustrated in Figs. 1 to 3 inclus ve, may have its body out or split into two simllar halves which may be clamped together upon the bushing 1 by bolts 7 or may be otherwise separably associated with a bushing or shaft on which it isto be used.

A pulley constructed as above described is cylindrical in form and effectually acts to keep its cooperating belt centrally in posi-- tion upon it without permitting it to shift laterally. This action I have found to be due to the fact that the surface of the thick layers or sections 4 quickly becomes slightly worn away or removed so as to expose the edges of the relatively harder layers 5, which thereupon act in effect like a series of crowned faces tending to hold the belt in place and particularly to keep it from moving sidewise. At the same time the surface of the sections 4 coacts with the belt in the ordinary manner so that crowning is not necessary. As a consequence there is no uneven stretching of the belt as is now the i caries.

case with pulleys of the ordinary construetion so that its life is materially prolonged. At the same time the pulley is durable and highly efiicient, particularly since the em posed edges of the hard sections 5 tend to reduce to a minimum the circumferential slipping of the belt.

It is to be understood that while I preferably use for the body of my pulley alternated layers or laminations of hard and soft woods, or of the same wood in which the grain is so. disposed as to cause uneven V wear, other materials having the same generalcharacteristics maybe also used with out departing from my lnvention, since by employing a pulley having a series of more tion consisting of alternated layers of hard and soft Wood. v a

2. A pulley having a body formed of a series of relatively soft sections With hard sections each consisting of a plurality of layers and alternating with the soft sections. 3. A pulley having a body formed of sec tions of relatively soft Wood and a plurality of sheets of Wood veneer interposed between each two adjacent sections, the grain in said sheetsrunning in different directions.

Ari-pulley having its body composed of relatively thick layers of Wood alternated with thin sheetsof WOOCl having greater Wear-resisting qualities than those of the thick layers.

5IA pulley having a body consisting of a series of Wood sections With sections of relatively harder Wood alternated therewith. 6. A pulley body consisting of relatively thick layers of relatively soft Wood'having alternated With them hard Wood sections each composed of a plurality of sheets of WOOd veneer all connected into a single rigid structure.

7. A pulley 'body' consisting of relatively thick layers ofrelatively softwood having alternated with them hard WOQCl sections each composed of a plurality of sheets of wood veneer all connected into a single rigid structure; with bolts running parallel to the axis of the pulley and tyingsaid parts together. l v

HAROLD E. PRINTZ. 

